In my opinion, for example, we should swap out unemployment/unemployment rate data with in-migration data. We should be far more deliberate about measuring a community's ability to attract people (including immigrants) as that is the new labour force metric that matters most.

The Urbanophile prefers net migration, but I've all but given up on anything considering out-migration and its unfortunate relation, brain drain. I take the contrarian view that greater rates of out-migration for regions and cities are usually a sign of good health. Of course, the exodus from Pittsburgh during the 1980s indicated acute economic distress. But even in that case, the ability of Rust Belt human capital to relocate where opportunity is more abundant is generally a testament to the quality of the talent.

The ability of an alpha world city to continue to draw the best and brightest despite the relatively high cost of living is impressive. Yet I'm still suspicious of the overall value ascribed to in-migration. The rub is chain migration. Pioneers may be guilty of rational choice, but those who follow are often moving along the path of least resistance. I suspect that leaving home is often an irrational consideration. Playing Odysseus is nothing new. But the pooling of adventurers in a shrinking number of global places is a geography unique to contemporary times.

Does your region's prodigal daughters and sons go to the same places others move? If I had a year's worth of funding, then I'd study the out-migration profiles of every Rust Belt city. I'd also be curious about the in-migration profiles. How many cities are like Pittsburgh with so much talent exchange with the DC MSA? Perhaps I don't need to remake the wheel. Is anyone mapping the urban migration connectivity profiles of US cities? How many brains are actually leaving the Rust Belt?